Sherburne w



(No Model.)

s. W. BURNHAM. I PHOTOGrlMUPHIG DEVELOPIPIG TRAY.

N0. 363,505. Patented May 24, 1887.

UNITED STATES PATENT OFFICE.

SHERBURNE W'. BURNHAM, OF CHICAGO, ILLINOIS, ASSIGNOR TO GAYTON A. DOUGLASS, OF SAME PLACE.

PHOTOGRAPHIC DEVELOPING-TRAY.

SPECIFICATION forming part of Letters Patent No. 363,505, dated May 24, 1887.

Application filed March 15, 1887. Serial No. 230.939. (No model.)

To all whom it may concern:

Be it known that I, SHERBURNE W. BURN- HAM, a citizen of the United States, residing in Chicago, in the county of Oookand State of Illinois, have invented a new and useful plate in a vessel and submerges it with the developing-fluid, watching it through the fluid as the process of' development advances, and taking the plate out from time to time to observe it by transmitted light until the image has been properly brought up. In order to readily take the glass negative-plate out of the tray containing the developingfluid various devices have, been-resorted to. Among other contrivances a thimble has been made to fit the finger and having a slender blade which might be readily forced under the plate, between it and the bottom of the tray. Wire clasps to secure to the plate have also been devised. The objection to such appliances has been the danger of accidental injury to the soft gelatin film. Another method has consisted in making raised ribs or pins on the bottom of the tray for the plate to rest upon, so that it shall be somewhat elevated from the bottom to enable the finger to catch the plate. The objection to this form of tray is, first, that it necessitates a considerably greater quantity of developing-fluid to properly cover the elevated plate, and, secondly, the agitation of the tray, which is both customary and desirable in the operationof' development, in order to effect a more uniform and rapid action, causes the fluid to flow under the plate, of course, as well as over it, and by carrying air with it under the plate produces bubbles in the developer that oftentimes seriously interfere with the operation.

To overcome these several difficulties in a simple and effective manner is the object of the present device.

I makea fiat-bottomed tray, which may be of glass and have a rectangular shape, with slightly-flaring sides and of proper size to receive the plate, allowing a little margin at one end.

The flat bottom of the tray is supported in a horizontal position by the under surface, so that the developing-fluid will evenly cover the plate when placed in the tray, and for this reason the supports on the under side of the bottom are made parallel to the surface of the bottom, so that when the tray is set upon a horizontal table or support the bottom may be horizontal. At one end in this flat bottom I form a narrow shallow median groove large enough to receive the finger-tip and extending midway of the bottom for such distance as to underlie for some extent any sized negative-plate that may be likely to be developed in thetray. This grooove may be repeated at each end or extend the whole length of the bottom; but I prefer it only at one end and only long enough to underlie the ordinary plate to be developed in the tray. This narrow shallow groove requires very little fluid to fill it and permits no bubbleproducing currents in agitation of the tray. When the plate is to be removed, the groove allows the finger-tip to engage the edge and push the plate until it encounters the outerso end of the tray, when the plate may be tipped up and conveniently grasped by the fingers.

- As the negative lies fiat on the bottom of the tray, no extra amount of developing-fluid is required, and a very small amount will suffice. 1

In the accompanying drawings, which form a part of this specification, and in which similar letters of reference indicate like parts, Figure 1 is a perspective view of my improved 9o tray. Fig.2 is a vertical centrallongitudinal section of same on the line'2 2 of Fig. 1, and Fig. 3 is a cross -section on line 3 3 of Fig. 1.

In said drawings, A is the fiat bottom of the tray, B B the sides, 0 G the ends. D is the bottom, said bottom being provided with a narrow shallow finger groove, and E reprenarrow shallow finger-groove, substentiallyas :o

sents a negativeplate. specified.

If desired, the tray may be made with the T 1 T v V 5 usual pouring-lip; but I find the cornerof the SHERBURBE LUIUL rectangular tray to form a convenientlip itself. Witnesses:

I claim- J OHN W. 1\[UNDAY,

The developingtmyhaving ahorizontal flat l- H. M. MUNDAY. 

